<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>三列布局</title>
<style>
body{ margin:0; padding:0; font-size:30px; font-weight:bold}
div{ text-align:center; line-height:50px}

#top{
	width: 100%;
	height: 100px;
	background-color: #3c3c3c;
}

#main{
	width: 100%;
	overflow: hidden;
}
.left{
	width: 30%;
	height: 600px;
	float: left;
	background-color: red;
}

.left{
	width: 70%;
	height: 600px;
	float: right;
	background-color: blue;
}

#bottom{
	width: 100%;
	height: 100px;
	background-color:#000;
}



</style>
</head>

<body>
	
	<div id="top"></div>
    <div id="main">
    <div class="left">left</div>
    <div class="right">right</div>
    </div>
    <div id="bottom"></div>
</body>
</html>
